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> It's also home to one of the biggest transportation deserts in the city, which will be functionally unlocked in the next five years or so once self-driving ca

> It's also home to one of the biggest transportation deserts in the city, which will be functionally unlocked in the next five years or so once self-driving cars are a thing. Self-driving cars don't magically make other cars, self-driving or not, vanish from the roads and they certainly can't match the raw throughput of moving thousands of people in a single train on a dedicated right of way.

Alex3917 8y ago
> Self-driving cars don't magically make other self-driving cars vanish I mean that's what they're supposed to do, if they can all drive one behind another at a constant speed without crashing or creating traffic jams. But more importantly, if you can be doing work while your car is driving itself then your effective commute is zero. And if your car can park itself in the suburbs, then that creates yet more space in the city that can be used to create housing. Self-driving cars, if they actually work, should radically reduce housing costs -- both by making formerly unlivable places suitable for residential buildings, and by freeing up significant amounts of land.
- lancewiggs 8y ago
  You've described a train or buses.
- jacques_chester 8y ago
  My point being that they don't make other cars vanish and they certainly don't make human-driven cars vanish in any sensible timeframe. On a person-kilometre-minute basis, cars are absurdly inefficient. Stupendously so. A typical subway train typically runs to about 157 metres. A 2018 Camry runs to about 5 metres. That gives about 31 car lengths for the subway car. Assume that every Camry is fully loaded with 5 passengers. That's 155 people. In the ideal condition, driving bumper-to-bumper with no other cars, 155 people in 157 metres -- about a person per linear metre. Here's the fun bit: the passenger capacity of an R142A carriage is 176. Not the whole train. One subway car. One subway car, approximately 16 metres long, holds more people than an entire train's length of self-driving Camrys driving with zero tolerance. Now add the fact that the trains have dedicated rights of way and note that even with the profound multi-decadal mess made of the MTA you simply cannot replace the subway with any other mode of transportation, not now, not ever. Self-driving cars don't repeal the laws of physics and they don't override Little's Law either.
  - CamperBob2 8y ago
    Yes, rail offers unparalleled efficiency at transporting people from one place where they don't want to be to another place where they don't want to be.
    - jacques_chester 8y ago
      If you don't want to be in place A or place B, how you get from A to B won't change things. For my own self, everywhere I want to go is served by the subway system. Often poorly, but that's a rip on the political history of the MTA, not on the nature of subways in general. If you closed the subways, New York would seize up and die. In fact we're going to get a taste of what a minor arterial clot is like when the L shuts down next year.
      - CamperBob2 8y ago
        If you don't want to be in place A or place B, how you get from A to B won't change things. You do that by not going there in the first place. A properly-designed network of self-driving cars would be a train. One that is always there when you need it, one that inherits the vast scale of existing infrastructure, and one that isn't vulnerable to paralysis through single points of failure. But as the posts on here tend to emphasize over and over again, no one has the vision to make this happen. HN's love affair with fixed rail is nothing less than one of history's great irrational obsessions. Public transportation is the one engineering discipline where solutions based on technology are "pedantic nonsense," while literally binding and constraining entire cities with hardware straight out of the Civil War era is considered the height of progress.
        jacques_chester 8y ago
        > A properly-designed network of self-driving cars would be a train. No, it wouldn't, for the reason I describe. Cars occupy too much space per person by a factor of about 11x times on the figures I gave further up. Self-driving cars will be part of the mix but they physically cannot replace the subway.
- romed 8y ago
  If you have an infinite spreading plane of cars moving all in the same direction at the same speed, and if nobody wants to join or leave this infinite plane of cars, and if none of the cars ever breaks down or runs out of energy, then this works perfectly. Back here on Earth it's not going to solve anything.
- skksjsnaahs 8y ago
  > if you can be doing work while your car is driving itself then your effective commute is zero That’s a big if. I’ve commuted in an Uber pool many times and hardly ever see any of the other passengers working. Most of them seem to be going to/from the office like me. Working on a rail commute seems more common. The smoother ride lends itself better to laptop work.
  - mathgeek 8y ago
    Another big if here is that your company considers that time to be on the clock. A commute that takes away family time without it counting towards your working time is still a commute. Getting more work done =/= not having a commute.
CydeWeys 8y ago
They also don't make pedestrians or cyclists disappear from the roads -- these are ever-present in NYC. It's gonna be a hassle for self-driving cars.
- jacques_chester 8y ago
  Indeed, cars trained on data gathered in California and Nevada are going to need a fair amount of tweaking to understand that pedestrians are a bit pushier hereabouts.
  - CydeWeys 8y ago
    I expect people to cotton on and jaywalk with impunity in front of self-driving cars, effectively always taking the right of way. Hell, this is probably as it should be. NYC would be better off with fewer cars and further prioritization of other modes of transport.

Alex3917 8y ago

> Self-driving cars don't magically make other self-driving cars vanish I mean that's what they're supposed to do, if they can all drive one behind another at a constant speed without crashing or creating traffic jams. But more importantly, if you can be doing work while your car is driving itself then your effective commute is zero. And if your car can park itself in the suburbs, then that creates yet more space in the city that can be used to create housing. Self-driving cars, if they actually work, should radically reduce housing costs -- both by making formerly unlivable places suitable for residential buildings, and by freeing up significant amounts of land.

lancewiggs 8y ago
You've described a train or buses.
jacques_chester 8y ago
My point being that they don't make other cars vanish and they certainly don't make human-driven cars vanish in any sensible timeframe. On a person-kilometre-minute basis, cars are absurdly inefficient. Stupendously so. A typical subway train typically runs to about 157 metres. A 2018 Camry runs to about 5 metres. That gives about 31 car lengths for the subway car. Assume that every Camry is fully loaded with 5 passengers. That's 155 people. In the ideal condition, driving bumper-to-bumper with no other cars, 155 people in 157 metres -- about a person per linear metre. Here's the fun bit: the passenger capacity of an R142A carriage is 176. Not the whole train. One subway car. One subway car, approximately 16 metres long, holds more people than an entire train's length of self-driving Camrys driving with zero tolerance. Now add the fact that the trains have dedicated rights of way and note that even with the profound multi-decadal mess made of the MTA you simply cannot replace the subway with any other mode of transportation, not now, not ever. Self-driving cars don't repeal the laws of physics and they don't override Little's Law either.
- CamperBob2 8y ago
  Yes, rail offers unparalleled efficiency at transporting people from one place where they don't want to be to another place where they don't want to be.
  - jacques_chester 8y ago
    If you don't want to be in place A or place B, how you get from A to B won't change things. For my own self, everywhere I want to go is served by the subway system. Often poorly, but that's a rip on the political history of the MTA, not on the nature of subways in general. If you closed the subways, New York would seize up and die. In fact we're going to get a taste of what a minor arterial clot is like when the L shuts down next year.
    - CamperBob2 8y ago
      If you don't want to be in place A or place B, how you get from A to B won't change things. You do that by not going there in the first place. A properly-designed network of self-driving cars would be a train. One that is always there when you need it, one that inherits the vast scale of existing infrastructure, and one that isn't vulnerable to paralysis through single points of failure. But as the posts on here tend to emphasize over and over again, no one has the vision to make this happen. HN's love affair with fixed rail is nothing less than one of history's great irrational obsessions. Public transportation is the one engineering discipline where solutions based on technology are "pedantic nonsense," while literally binding and constraining entire cities with hardware straight out of the Civil War era is considered the height of progress.
      - jacques_chester 8y ago
        > A properly-designed network of self-driving cars would be a train. No, it wouldn't, for the reason I describe. Cars occupy too much space per person by a factor of about 11x times on the figures I gave further up. Self-driving cars will be part of the mix but they physically cannot replace the subway.
romed 8y ago
If you have an infinite spreading plane of cars moving all in the same direction at the same speed, and if nobody wants to join or leave this infinite plane of cars, and if none of the cars ever breaks down or runs out of energy, then this works perfectly. Back here on Earth it's not going to solve anything.
skksjsnaahs 8y ago
> if you can be doing work while your car is driving itself then your effective commute is zero That’s a big if. I’ve commuted in an Uber pool many times and hardly ever see any of the other passengers working. Most of them seem to be going to/from the office like me. Working on a rail commute seems more common. The smoother ride lends itself better to laptop work.
- mathgeek 8y ago
  Another big if here is that your company considers that time to be on the clock. A commute that takes away family time without it counting towards your working time is still a commute. Getting more work done =/= not having a commute.

CydeWeys 8y ago

They also don't make pedestrians or cyclists disappear from the roads -- these are ever-present in NYC. It's gonna be a hassle for self-driving cars.

jacques_chester 8y ago
Indeed, cars trained on data gathered in California and Nevada are going to need a fair amount of tweaking to understand that pedestrians are a bit pushier hereabouts.
- CydeWeys 8y ago
  I expect people to cotton on and jaywalk with impunity in front of self-driving cars, effectively always taking the right of way. Hell, this is probably as it should be. NYC would be better off with fewer cars and further prioritization of other modes of transport.